def test_first():
colors = SingleLinkedList()
colors.push("Cadmium Red Light")
assert colors.first() == "Cadmium Red Light"
colors.push("Hansa Yellow")
assert colors.first() == "Cadmium Red Light"
colors.shift("Pthalo Green")
assert colors.first() == "Pthalo Green"
def test_first(self):
colors = SingleLinkedList()
colors.push('Cadmium Red Light')
assert colors.first() == 'Cadmium Red Light'
colors.push('Hansa Yellow')
assert colors.first() == 'Cadmium Red Light'
colors.shift('Pthalo Green')
assert colors.first() == 'Pthalo Green'
def test_first():
colors = SingleLinkedList()
colors.push('red')
assert colors.first() == 'red'
colors.push('yellow')
assert colors.first() == 'red'
colors.push('blue')
assert colors.first() == 'red'